The present invention relates generally to equipment for closing cases containing goods for shipment, and particularly to that type of equipment adapted for folding the top flaps of such cases to overlapping closed positions.
In automated assembly line packaging techniques, there remains a need to quickly and efficiently fold the flaps of square or rectangular-shaped cases to a closed position and maintain that position for a period of time sufficient to allow the glue, which has been previously applied to certain flap surfaces, to set. The case may then be advanced in the assembly line for further processing or shipment.
Conventional packaging cases which are in wide-spread use are generally rectangular in shape and include sets of top and bottom flaps. After having been erected from a blank into a box-like configuration, glue is applied to specified surfaces of the bottom flaps which are then folded and held in that position until the glue is set. This process can be carried out either manually or by machine and is not overly difficult since the case is empty at this stage and pressure can be applied from above and below so as to sandwich the bottom flaps in the closed position until it is assured that the glue is set. A machine specially adapted for erecting a folded blank into a box configuration, applying glue to the bottom flaps and folding the same, is fully disclosed in my copending application by James A. Goodman, U.S. Ser. No. 371,945 filed Apr. 26, 1982, and assigned to the assignee of the present invention.
The process of closing the case top is, however, not as easily accomplished. Equipment access from inside the erected case, to hold the top flaps sandwiched together in a closed position, is precluded. If the contents fill the erected case to the top, and if such contents are solid, external pressure from above alone may be effective to press the top flaps against such contents until the glue is sufficiently dried. Such an unpredictable arrangement is unacceptable for high-speed commercial sealing operations. Without predictable supporting during the glueing operations, the top flaps cannot be sealed effectively in that fashion.
The present invention is especially advantageous in situations where the contents of the case are fragile, such as packages of coffee, potato chips or popcorn, and when the contents, whether fragile or otherwise, do not fill the entire volume of the case. The present invention permits one set of flaps, such as the top minor flaps, to be folded to a closed position and supported there while the other flaps, such as the major flaps, are folded and firmly pressed down on the glued minor flaps until such glue is set. Moreover, the first set of flaps are supported in this closed position from above the case without interfering with the closing of the top flaps thereover. Other advantages and features of the invention will become apparent by referring to the detailed description of the invention.